# How to calculate the phase margin from Bode Plot if only the phase angle corresponds to the pole frequencies are given?

I have a Bode plot where only the phase angle corresponds to the two pole frequencies are given. The value of gain crossover frequency where the loop gain is unity is unknown.

$$\mathrm{PM} = \phi - (-180^{\circ})$$

I know PM can be calculated by checking the usual formula as above, but what could be the other criteria for performing this solution? Is the phase margin going to 180 degrees for this two pole (I assume it is 2 pole system as only two poles are given, you can correct me if I am wrong here)? Or, is it going to be (180+(-90-45-135) = -90? The transfer function could be

$$H(s) = \frac{1}{(s+\omega_{p1})(s+\omega_{p2})}$$